PubMed HealthSearch

Biomedical subjects

M Galloni

Publications and source records attributed to M Galloni.

15 recordsLinked to original sources

Surgical technique for artificial mitral chordae implantation.

Failure of reconstructive procedures of the mitral valve is often ascribed to diffuse alteration of the subvalvular apparatus, which prevents the utilization of well-established techniques such as chordal transposition or shortening. For this reason, in 1986 after 2 years of animal experiments, we started the clinical use of expanded-polytetrafluoroethylene mitral chordae. Details of the surgical procedure are presented. Our experience is based on 51 patients with a mean follow-up of about 20 months (range 3-57). Four patients had the valve replaced during the same operation: one patient died later of cardiac failure and two underwent reoperation, 8 and 18 months after operation. Forty-one patients are in New York Heart Association Functional Class I and three in Class II. We suggest this technique in association with other traditional procedures to increase the number of mitral valves repaired, mostly because of degenerative etiology.

Adult

Calcification of chemically treated bovine pericardium.

One of the most important problems arising in cardiac bioprostheses made with bovine pericardium and, more generally, with biologically-derived tissues is tissue calcification. The present study assessed four chemical treatments on patches of bovine pericardium, intended to avoid or minimize calcification. Pericardium specimens were treated with: A) 0.5% glutaraldehyde; B) 0.5% glutaraldehyde + 4% formaldehyde; C) same as A, but with a further neutralization treatment; D) acylation of fresh bovine pericardium. Circular samples of 1 cm diameter were subcutaneously implanted in the abdominal region of three groups of six rats. The explants were retrieved after 2, 4 and 8 weeks. The calcium content and the histological results showed better behaviour for C and D samples than with the commonly used fixation methods (A and B). The lowest calcification was observed with treatment D, even though its morphological structures were somewhat modified with homogenation of collagen bundles. Among the glutaraldehyde-based treatments, treatment C appears to be the most promising because the pericardium shows slower calcium accumulation with a diffusive pattern.

Animals

Artificial mitral valve chordae: experimental and clinical experience.

Failure of mitral valve reconstructive procedures often may be ascribed to severe or progressive alterations of subvalvar apparatus. Expanded polytetrafluoroethylene sutures were used to replace anterior leaflet mitral valve chordae in 8 animals (hypertensive dogs and growing sheep). After the positive results obtained during a 13-month follow-up, 5-0 sutures of the same material were introduced in clinical practice to replace mitral valve chordae. Twelve patients had two to six anterior leaflet chordae replaced for degenerative or rheumatic disease. In 3 patients, the intraoperative result was not acceptable and a prosthetic valve was inserted during the same operation. One case of late failure has been recorded so far (18 months after the procedure), owing to rupture of a natural chorda shortened at operation. Since that event, we have implanted supportive artificial chordae in case of diffuse alteration of natural chordae. The remaining patients show satisfactory hemodynamic results, and no valve-related events have been recognized up to 30 months after operation. We suggest use of 5-0 polytetrafluoroethylene sutures in replacing anterior leaflet chordae in degenerative, rheumatic, and congenital mitral valve diseases.

Adult

Morphological comparison of primary tissue failure (PTF) in porcine mitral and aortic bioprostheses in the same patient.

Clinical and pathological studies have not clearly demonstrated whether primary tissue failure (PTF) in porcine bioprostheses occurs more often in the mitral than in the aortic position. We have studied morphological alterations in both positions in the same individual in 15 patients (14 mitroaortic and 1 mitroaortotricuspid) reoperated upon for PTF. Bioprostheses explanted were photographed, radiographed and observed in transmitted polarizing light. All lesions received a score on the basis of morphological criteria. The creep of the stent was measured. Calcification was slightly heavier and the degree of creep was significantly greater in the mitral position. Tears, infiltration and pannus growth did not differ between the two positions. According to our study, there is no conclusive demonstration that bioprostheses degenerate earlier and more extensively in the mitral than in the aortic position.

Adult

Scanning electron microscopy of pathologic changes in the epithelial surfaces of the uterus and uterine tubes of cows.

Genital tracts from 15 cows with catarrhal and purulent inflammation of the uterus and uterine tubes, cystic hyperplasia of the endometrium, or hydrosalpinx were evaluated by the use of scanning electron microscopy to determine epithelial changes associated with these conditions. Uterine epithelium was revealed to be easily damaged, even in the course of mild inflammation, whereas epithelium of the uterine tube was more resistant.

Animals

The epithelial pathology of bovine genital tuberculosis.

The histopathology of the uterine and salpingeal epithelium of five cows affected with genital tuberculosis was studied. Both optical and scanning electron microscopy were used and the results were compared. Various forms and degrees of cellular lesions are described, including hypertrophy, flattening, detachment, nuclear protrusions and alterations of the cilia. In the different sites considered (uterus: intercaruncular and caruncular areas; salpinges: isthmus and ampulla) various characteristic lesions were observed.

Animals

Architecture of swine lymphnode: light- and scanning electron microscopical studies.

The overall architecture of the swine lymphnode was studied on: nodes injected for the visualization of the lymph pathway, serially sectioned nodes, and material processed for scanning electron microscopy. Despite the commonly reported scheme of the node architecture, cortical-like and medullar-like tissue appeared to be intermingled seemingly with no rules in the node substance. Thus it was not uncommon to find cortical-like tissue in a peripheral position like in other mammals. A scheme of the node organization is proposed and the features of the different components of the parenchyma are described with particular emphasis on the lymphatic sinuses and the lymph pathway. Finally, scanning electron microscopical data on swine nodes are discussed and comparison made with observations reported for other mammals.

Animals

Postoperative histological diagnosis in two cases of unsuspected bioprosthetic endocarditis.

Two cases of preoperatively unsuspected porcine bioprosthetic endocarditis are presented. Both cases, thought to be a sterile thrombosis and a primary tissue failure respectively, were correctly diagnosed only with histological examination. Cultures and histological examination of the explanted tissue are necessary for a definite diagnosis in every case of prosthetic malfunction.

Adult